The DuBois and DuBois formula2

A variation of DuBois and DuBois15 that gives virtually identical results is:

BSA (m2) = 0.007184 x Height(cm)0.725 x Weight(kg)0.425

So much about DuBois is doubles.

Huh? The chart below shows no significant difference between Mosteller and DuBois.

This chart shows 33 adult cancer patients, comparing their BSA calculated with the methods of Mosteller and DuBois. The patients were pre-sorted into ascending order of BSA. The data points are so close to each other, the lines overlap each other.

The Haycock formula3

BSA (m2) = 0.024265 x Height(cm)0.3964 x Weight(kg)0.5378

I have a photographic memory. Let me try to memorize these.

Done! No, nevermind, it’s gone.

The Gehan and George formula4

BSA (m2) = 0.0235 x Height(cm)0.42246 x Weight(kg)0.51456

Once, I took a speed reading course, and read War and Peace. It involves Russia.

The Boyd formula5

The Mosteller formula is recommended6. To learn more about the issues and differences in BSA formulas, read the BSA standards report by Thanh Vu B.Sc(pharm). It explains why the Mosteller formula was adopted for use by the Pharmacy and Therapeutics Committee of the Cross Cancer Institute, Edmonton, Alberta, Canada.

Formula for Body Mass Index.

Body Mass Index = Weight(kg) / Height(m)2

Definitions of "overweight".

A Body Mass Index between 25 and 29.9 is "overweight", greater than or equal to 30 is "obese"7. However, some very muscular people can have high Body Mass Indexes and in adolescents, BMIs frequently result in overestimation of fatness. A better classification8 of "overweight" is given in this table below. These numbers are used in the BSA calculator.

Women

Men

underweight

<19.1

<20.7

ideal weight

19.1-25.8

20.7-26.4

marginally overweight

25.8-27.3

26.4-27.8

overweight

27.3-32.3

27.8-31.1

very overweight or obese

>32.3

>31.1

Weight Percentile, and Height Percentile, compared to the population.

An adult whose weight is at the 50th percentile, is at the average weight of the population. An adult at the 90th percentile is quite heavy.

A bit of history, you can ignore.

For calculating percentiles, the oldest version of the calculator used weight data from a study9 of 3992 consecutive adult cancer patients who underwent CT scanning. That study did not stratify males versus females, and it did not include pediatrics. By using the variance distribution from that study, and then adjusting the means to 79.4kg for males and 64.5kg for females, it was able to estimate the weight percentile. The height data came from a study10 of 600 randomly selected cancer patients. That study also did not stratify males versus females, and it did not include pediatrics. By using the variance distribution from that study, and then adjusting the means to 69 inches for males and 64 inches for females, the older calculator was able to estimate the height percentile.

The next version of the calculator used better data. Pediatric data was derived from standard pediatric growth charts, based on American 1979 data13. Adult data for median height and weight came from Canadian 1997 data11. The variances for height and weight and the weight for height data comes from Canadian 1971 data12. Americans tend to be a little taller and heavier than Canadians.

The most recent version of the calculator has switched to using exclusively American data from the NHANES III survey14 of 1988 to 1994. This data is used for the height and weight percentiles algorithm. It incorporates both adults and children’s data of heights and weights, the median (average) values and the variances (the range of fatness – thinness). Keep this in mind, that American’s tend to be taller and heavier than many other nationalities.

Boyd E, The growth of the surface area of the human body. Minneapolis: university of Minnesota Press, 1935. (I never found the original source. Instead, I copied the formula from: http://www.ispub.com/journals/IJA/Vol2N2/bsa.htm )